From BiblePortal Wikipedia

King James Dictionary [1]

FI'NER, n.

1. One who refines or purifies.  Proverbs 25:4 . 2. a. Comparative of fine.

Easton's Bible Dictionary [2]

 Proverbs 25:4 Judges 17:4  Isaiah 41:7

Webster's Dictionary [3]

(n.) One who fines or purifies.

Morrish Bible Dictionary [4]

See Refiner

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [5]

( צֹרֵ , Tsoreph',),:A gold and silver worker ( Proverbs 25:4). (See Refiner). In  Judges 17:4, our version renders the word "founder;" in  Isaiah 41:7, "goldsmith." It refers especially-to the melting of fine metal. (See Furnace). The Egyptians carried the working of metals to a very extraordinary degree of perfection, as their various articles of jewelry preserved in our museums evince; and there is no doubt the Hebrews derived their knowledge of these arts from this source, though there is at the same time reference to their being known before the Flood ( Genesis 14:19-22). (See Metal).